Field of the Invention:
This is a new process for making bispicolylamine from cyanopyridines and hydrogen. Palladium on carbon is used as the catalyst.
Prior Art:
Volkova et al. teach that cyanopyridines are hydrogenated in the presence of palladium (or palladium on carbon) to form the corresponding picolylamines (i.e., aminomethylpyridines). See Volkova et al.: Chemical Abstracts, 79: 42296n; 80: 120705g; 81: 49570x; 83: 28065n; and 83: 113388q. Matsumoto et al. (Chemical Abstracts, 82: 156097r) teach that 2,6-biscyanopyridines are hydrogenated to form the corresponding 2,6-bis(aminomethyl)pyridines as the trihydrochloride salts when the reaction is conducted over palladium on carbon using hydrochloric acid/methanol as the hydrogenation medium. These references indicate that palladium and palladium on carbon are very effective catalysts in the reaction and produce the corresponding picolylamines selectively. In view of this teaching, we were most surprised to discover that bispicolylamines could be produced selectively and in extremely high yields from the same reactant under the conditions set forth below.